IC443 - Jellyfish Nebula - RGB, and HaRGB (Kurt Zeppetello)

IC443 - Jellyfish Nebula - RGB, and HaRGB

Link: https://kurt-zeppetello.blogspot.com/

Recently, I shot the Jellyfish Nebula (IC 443) in the constellation Gemini. It is located near the star Eta Geminorum (Propus) and lies approximately 5,000 light years from Earth. It is suspected of being the remains of a supernova that occurred 3,000 - 30,000 years ago. Also interesting is that the same supernova event likely created the neutron star within this nebula (source: Wikipedia, APOD).

I first imaged it in Ha since the moon was out. This is what I am doing these days during full moon phases. I was able to get some RGB data this past week. I decided to use my Astronomik UHC clip-in filter since I have had good luck with these types of emission nebula.

This was a pleasant object to image as it is easy to locate being so close to Eta Geminorum (Propus). Also, since I imaged the RGB over to nights, I basically just had to open the shed and point to the nebula as I left everything as is, that is already focused. That being said, this was one of the most difficult images I ever processed. The Ha was easy enough but the color image was a big pain. The color of the main part nebula was highly differentiated and not in a good way, Propus and Tejat (the two large stars) had horrible halos, and the secondary tail (left hand side) barely was visible. Also, My Ha image did not frame up as well as I thought it would. I spent many hours bouncing back and forth between PS and LR2, usually I do PS then LR2 and a final touch in PS. This object is one where a really good monochrome camera would be preferable as opposed to a DSLR. Most of the really good images of this object were taken with a dedicated astrophotography camera. Anyway, I am happy with how it finally turned out.

A - RGB

B - HaRGB

C - HaRGB-V2 (adjusted for older monitors)

Original
B
Final
C

B

Description: HaRGB version!

Uploaded: ...

C

Description: Adjusted the offset and gamma correction a bit. The former image looked fine on my computer, i-phone, and etc, but on my old computer it looked awful. I have to do this frequently I wish all monitors were the same...

Uploaded: ...

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